In the field of civil engineering works that excavates earth, stone and so on, construction machines such as a hydraulic excavator (excavator) have been used in works.
This type of hydraulic excavator mainly includes a lower traveling unit, an upper revolving unit that is revolvably mounted to the lower traveling unit, and an operator compartment (cab) that is fixedly arranged on the upper revolving unit and accommodates an operator.
For example, Japanese Patent Laid-Open Publication TOKUKAI No. 2004-306893 published on Nov. 4, 2004) discloses a cab structure that is deviated from the revolving center of an upper revolving unit that is arranged on the lower traveling unit, and that includes a slide door that is disposed on the exterior side surface and is formed in a curved surface that bulges outward. The cab structure can ensure roll-over (toppling) measures strength at low manufacturing cost. Japanese Patent Laid-Open Publication TOKUKAI No. 2004-224083 and Japanese Patent Laid-Open Publication TOKUKAI No. HEI 11-200412 also disclose known cab structures for construction machine.